//
//  CalculatorModel.h
//  Calculator
//
//  Created by Wu Ting on 13-4-16.
//  Copyright (c) 2013年 Wu Ting. All rights reserved.
//

#import <Foundation/Foundation.h>

@interface CalculatorModel : NSObject

- (void) pushOperand:(double)operand;
- (double) performOperation: (NSString *)operation;

@end
